Research supposedly supports the preference of mocker females for males with a wide repertoire.  Perhaps choosing a good mimic means she chooses a male who is mature, experienced, and intelligent, and mating with him gives her preferences genetic advantage, as well as giving his mimicry ability a genetic advantage.  I hope I'm not butchering an explanation of heritability of sexual attractiveness.   Perhaps a scientist on the list will help out.  
June Newman,
Carroll County

On Jun 10, 2008, at 11:05 AM, Bill Osborne wrote:

Love Mockingbirds.  Have heard Mockingbirds will sing all night when the female is on the nest.  
Has anyone an idea of why these birds do the imitations?  

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